Selecting device



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SELECTING DEVIC E w. DALLENBACH Filed Dec. 29, 1933 Patented pr. 6, i937 actress SELECTING EWGE 1 Walter Dttllenbach, Berlin-Charlottenburg, Germany, assignor to N. V. Machincrieen-en apparatcn Fabrieken Meat, Utrecht, Netherlands Application December 29, 1933, Serial No. 704,56

Germany January 3, 1933 5 Claims... (@i. I invention relates to a device for selecting As long as the discharge current of condenser recelvers over a common connecting line. or increases, the negative charge of grid I12, and

The invention represents an electric analogy therefore the stopping action, is increased. As to the start-stop principle used in the communisoon as the discharge current of condenser 01 5 cation art for synchronizing transmitters and begins to fade away, the direction of the electro- 5 receivers as, for instance, in telegraphs, whereby motive force at the secondary winding of the. synchronized alternating current networks at the transformer 161 changes and the grid hz becomes transmitting and receiving points are saved; positive. At the same time, the non-conducting By way of example, the invention is illustrated gas path (12-402 becomes conductive, while the in the accompanying drawing. gas path G1-k1 is rendered non-conductive as 10 Referring to the drawing, a battery 9' charges a result of the termination of the discharging over the resistances r1, r2, r3, T4 the condensers of condenser 01. c1, c2, c3, 04 connected in series with the trans- In similar manner, conductor 02 now begins to formers ur, M2, H3, H4 and the valves provided with discharge and, shortly before this terminates, it

15 the control grids h1, ha, ha, hr, the anodes starts the discharge of condenser 03 which, in 15 (11, as, as, a; and the hot cathodes R1, kg, R3, 764. turn, starts the discharge of condenser 04. It is The valves are gas-filled, so that, when the blookclear that this principle of successive discharging ing ceases even for a short period, the control of condensers may be extended to include any valve will retain its conductivity until the current desired number. After the last condenser has has reached zero. The ends of the secondary discharged, the distributor is stopped until it is 20 windings of the transformers 'lLr, 1L2, us, Us are started again by the application of another synconnected with the receivers e1, e2, e3, e4. One chronizing impulse to conductor L.

end of the secondary winding of the transformers The sequence of discharge operations described is connected over a choking coil or throttle s2, S3, above thus causes ne f th p r llel r i s S4, with the control grid of the following tube. 61,114, (1 1, k1, 02, team, k2, etc. to become conductive 25 The grid hi of the first valve cell is negatively from time to time, whereby it is accessible to the 1 biased by the battery nand the resistance 1. high frequency currents which are impressed on L represents the line coming from the transthe conductor L between two synchronizing imformer (not shown) which line is adapted to pulses, and which pass through the transformer transmit high frequency impulses. 22. Accordingly, by sending a signal impulse over 0 Condensers w and t are connected in parallel conductor L from the high frequ y impulse to the grid resistances f and z, in order to create which starts the discharge of the condenser 01, a convenientpath for the. alternating currents. it beco es p s y Suitable time intervals to The sender may consist of any desired device cause said signal i p o act c v y which is adapted to send out high frequency imthrough condensers c1, c2, c3, or on transformers 35 pulses along conductor L at certain successive ui, uz,'ua, m and thus on receivers e1, e2, e3, e4. time intervals. Assume, for example, that while condenser ca The device operates as follows: is discharging, high frequency impulses, for ex- It is assumed at the outset that conductor L ample, in telegraphic rhythm, are impressed 40 receives only synchronization impulses, and no upon conductor L. Thesehigh frequency im- 40 signal impulses. This synchronization high frepulses are transmitted through transformer p l quency impulse sent out from the sender is tothe circuit p, c3,u3,a3,kz,p, and through transtransmitted through the transformer q to the former Us to the high frequency receiver congrid in of. the first valve-tube and neutralizes, nected to the secondary winding thereof. The although only temporarilygthe negative charge high frequency choking coil or throttle S4 pre- 45 of the grid in. This renders the gas path (l1.]1 vents the high frequency from acting or being conductive, and closes a discharge circuit for the impressed on grid hr of the next tube. Accordcondenser 01 through m, (01, ki, 11. The discharge ingly, the discharge current of the condenser ca current of condenser 01, which first rises and then is in the primary and secondary winding oftrans- 'falls, induces a low frequency voltage impulse in former as, and also the high frequency impressed 50 the secondary winding of transformer 114, which onto the conductor L during the discharge of this leaves the high frequency receiver unaffected, condenser, said current and frequency being but which acts on the grid hz of the second superimposed on each other. The choking coil valve-tube back to the secondary winding of 11.1 by or throttle S4 effects a separation in that only the way of 52, ha, ha, fw. discharge current affects the grid potential of 55 the folowing valve tube, while the high frequency is taken up in the high frequency receiver e3.

The duration of the individual discharges must be balanced by the size of the condensers, load 5 resistances and discharge lines in such manner that the total duration of-the discharge impulse arising in the parallel conductor channels is smaller than the period of synchronizing impulse of the sender.

Actuating can take place by wireless instead of through the line L.

I claim:-

1. A distributor for selectively distributing signals received over a common connecting line comprising a plurality of normally non-conducting channels, a coupling transformer connecting said chanels in parallel with the connecting line, each channel consisting of a condenser for the signal impulses and a grid-controlled discharge tube, means responsive to an initial impulse received over said connecting line for initiating operation of the grid controlled discharge tube in the first channel whereby said channel becomes conductive, and means responsive thereto for/rendering the remaining channels successively conductive.

2; A distributor for selectively distributing signals received over a common connecting line, comprising a plurality of normally non-conducting channels,' a coupling transformer connecting said channels in parallel with the connecting line, each channel including a condenser for the signal impulses, a grid-controlled discharge tube, and a high ohmic resistance, a common source of potential for charging said condensers over the resistances, means responsive to an initial impulse received over said connectingline for initiating operation of the grid controlled discharge tube in the first channel, said discharge tubes being adapted to discharge the condensers,

transformers, the primary coil of the transformers in series with the discharge channels, receivers, each secondary .coil of sai'd't-transform'ers being connected with a receiver.

3. A distributor for selectively distributing signals received over a common connecting line comprising a plurality of normally non-conducting channels, a coupling transformer connecting said channels in parallel with the connecting line, each channel consisting of a condenser for the signal impulses, a grid-controlled discharge tube, and a highohmic resistance, a common potential source for charging said condensers over the resistances, transformers, the primary coil of each transformer being in series with a discharge channel, receivers, each secondary coil of said last-named transformers being connected with a receiver, potential sources imparting a negative preliminary potential to said grids, said coupling transformer passing the initial impulse to the grid of the first tube, the secondary coils of said coupling transformer inducing potentials and nullifying the negative preliminary potential of the following tube grids of the series. I

4. In a distributor as claimed in claim 3, chok' ing coils in the second and each following grid line.

ing coils in the second and each following grid line, each of said control grids being connected with the secondary winding of the preceding transformer.

WALTER DALLENBACH.

51 In a distributor as claimed in claim 3, chok- 

